Polarized light transport in anisotropic media composed of ellipsoids: Influence of structural anisotropy. (April 2020)

• Record Type: Journal Article
• Authors: Liu, X.J.; Chen, X.W.; Zhao, C.Y.; Wang, B.X.
• Is Part Of: Journal of quantitative spectroscopy & radiative transfer. Volume 245(2020)
• Publication Date: 2020-04
• Subjects: Polarized light -- Structural anisotropy -- Ellipsoid -- Mueller matrix -- Depolarization; Spectrum analysis -- Periodicals; Radiation -- Periodicals; Analyse spectrale -- Périodiques; Rayonnement -- Périodiques; Radiation; Spectrum analysis; Periodicals; 543.0858
• DOI: 10.1016/j.jqsrt.2020.106854
• Languages: English
• ISSNs: 0022-4073

Abstract

Highlights: Variations in image-based Mueller matrix encode information about the aspect ratio, and orientation of ellipsoidal scatterers. The rate of depolarization depends on the incident polarization state, scattering orders and the anisotropy of the random medium. Structural anisotropy decelerates the depolarization rate of scattering light. Structural anisotropy has different effects on depolarization of circularly polarized incidence and linearly polarized incidence. Traditional diffusion theory cannot be used to solve polarized light transport in anisotropic media. Abstract: In this study, the propagation of polarized light in anisotropic media composed of prolate ellipsoids oriented in the same direction is investigated. We proposed a DDA-Monte Carlo combined algorithm to solve the radiative transfer problem. By comparisons of backscattering two-dimensional images of Mueller matrix, the results show that, the changing information of aspect ratio and orientation of ellipsoidal scatterers can be well encoded in image-based Mueller matrix. Moreover, the effect of aspect ratio and orientation on diattenuation, retardance, depolarization and linear retardance are demonstrated by decomposing the Mueller matrix. Furthermore, the impact of aspect ratio on the rate of depolarization of linearly and circularly polarized light with optical thickness has been construed. This study has proved that structural anisotropy decelerates the depolarization rate of scattering light and traditional diffusion theory cannot be used to solve polarized light transport in anisotropic media. Our study can promote a further research on the physics of radiative transfer in anisotropic media.